parallelism with xargs

gistfile1.txt

#!/bin/sh

if [ -z "$1" ]
then
	# Query N load balancers in parallel.
	xargs -P 10 -n 1 -d '\n' $0 poll <<EOF
	10.0.0.1	community101 dc=foo1 host=lb01.foo.com
	10.0.0.2	community101 dc=foo1 host=lb02.foo.com
	10.0.0.3	community101 dc=foo1 host=lb03.foo.com
EOF
	exit
fi

if [ "$1" != "poll" ]
then
	echo >&2 "usage: $0"
	echo >&2 "       $0 poll <addr> <password> <tags>"
	exit 1
fi

set -- $*
shift
addr=$1; shift
pass=$1; shift
tags=$*

datadir=$(mktemp -d /tmp/netscaler.XXXXXX) || exit
cd $datadir || exit

http=".1.3.6.1.4.1.5951.4.1.1.48"
comp=".1.3.6.1.4.1.5951.4.1.1.50"
ssl=".1.3.6.1.4.1.5951.4.1.1.47"
tcp=".1.3.6.1.4.1.5951.4.1.1.46"

#
# The code section between t0 and t1 is time-critical.
# This justifies job control tricks.
#
t0=$(date +%s)
snmpwalk -v2c -c $pass -Oneq $addr $http >a &
snmpwalk -v2c -c $pass -Oneq $addr $comp >b &
snmpwalk -v2c -c $pass -Oneq $addr $ssl >c &
snmpwalk -v2c -c $pass -Oneq $addr $tcp >d &
wait; wait; wait; wait
t1=$(date +%s)
cat a b c d >data

delta=$(expr $t1 - $t0)
if [ $delta -gt 1 ]
then
	echo >&2 "$addr: query took $delta seconds"
fi

# V looks up specified oid value in snmp data dump.
v() {
	_v=$(sed -n "s/^$1 //p" < data)
	if [ -z "$_v" ]
	then
		echo >&2 "$addr: missing oid $1"
	fi
	echo $_v
}

echo "netscaler.http.request.received $t0 $(v $http.45.0) $tags type=get"
echo "netscaler.http.request.received $t0 $(v $http.46.0) $tags type=put"
echo "netscaler.http.request.received $t0 $(v $http.47.0) $tags type=other"
echo "netscaler.http.request.bytes $t0 $(v $http.48.0) $tags"
echo "netscaler.http.request.errors $t0 $(v $http.57.0) $tags type=HeaderTooLong"

echo "netscaler.http.response.sent $t0 $(v $http.53.0) $tags"
echo "netscaler.http.response.bytes $t0 $(v $http.51.0) $tags"
echo "netscaler.http.response.chunking $t0 $(v $http.62.0) $tags chunked=true"
echo "netscaler.http.response.chunking $t0 $(v $http.63.0) $tags chunked=false"
echo "netscaler.http.response.compressed $t0 $(v $comp.1.0) $tags"
echo "netscaler.http.response.errors $t0 $(v $http.58.0) $tags type=HeaderTooLong"
echo "netscaler.http.response.errors $t0 $(v $http.61.0) $tags type=5yz"

echo "netscaler.ssl.sessions $t0 $(v $ssl.205.0) $tags version=ssl2"
echo "netscaler.ssl.sessions $t0 $(v $ssl.206.0) $tags version=ssl3"
echo "netscaler.ssl.sessions $t0 $(v $ssl.207.0) $tags version=tls1"

echo "netscaler.ssl.transactions $t0 $(v $ssl.201.0) $tags version=ssl2"
echo "netscaler.ssl.transactions $t0 $(v $ssl.202.0) $tags version=ssl3"
echo "netscaler.ssl.transactions $t0 $(v $ssl.203.0) $tags version=tls1"

echo "netscaler.ssl.bytes $t0 $(v $ssl.312.0) $tags mode=encrypt"
echo "netscaler.ssl.bytes $t0 $(v $ssl.309.0) $tags mode=decrypt"

echo "netscaler.ssl.events $t0 $(v $ssl.209.0) $tags type=SessionCreate"
echo "netscaler.ssl.events $t0 $(v $ssl.210.0) $tags type=SessionReuse"
echo "netscaler.ssl.events $t0 $(v $ssl.208.0) $tags type=SessionExpiry"
echo "netscaler.ssl.events $t0 $(v $ssl.213.0) $tags type=Renegotiation version=ssl3"
echo "netscaler.ssl.events $t0 $(v $ssl.214.0) $tags type=Renegotiation version=tls1"
echo "netscaler.ssl.events $t0 $(v $ssl.219.0) $tags type=ClientAuth version=ssl3"
echo "netscaler.ssl.events $t0 $(v $ssl.220.0) $tags type=ClientAuth version=tls1"

echo "netscaler.tcp.conns $t0 $(v $tcp.11.0) $tags state=Opening lbend=front"
echo "netscaler.tcp.conns $t0 $(v $tcp.12.0) $tags state=Established lbend=front"
echo "netscaler.tcp.conns $t0 $(v $tcp.9.0) $tags state=Closing lbend=front"
echo "netscaler.tcp.conns $t0 $(v $tcp.72.0) $tags state=Invalid"

echo "netscaler.tcp.packets $t0 $(v $tcp.61.0) $tags direction=in"
echo "netscaler.tcp.packets $t0 $(v $tcp.63.0) $tags direction=out"

echo "netscaler.tcp.bytes $t0 $(v $tcp.62.0) $tags direction=in"
echo "netscaler.tcp.bytes $t0 $(v $tcp.64.0) $tags direction=out"

echo "netscaler.tcp.events $t0 $(v $tcp.21.0) $tags type=SynReceived"
echo "netscaler.tcp.events $t0 $(v $tcp.25.0) $tags type=SynReceivedAtTimeWait"
echo "netscaler.tcp.events $t0 $(v $tcp.24.0) $tags type=FinReceived"
echo "netscaler.tcp.events $t0 $(v $tcp.28.0) $tags type=TimeoutIdleHandshake lbend=front"
echo "netscaler.tcp.events $t0 $(v $tcp.26.0) $tags type=TimeoutIdleClientOrServer lbend=front"
echo "netscaler.tcp.events $t0 $(v $tcp.30.0) $tags type=TimeoutIdleServerAfterClientFin lbend=back"
echo "netscaler.tcp.events $t0 $(v $tcp.32.0) $tags type=TimeoutIdleClientAfterServerFin lbend=front"

echo "netscaler.tcp.errors $t0 $(v $tcp.34.0) $tags type=ReceivedIncorrectChecksum"
echo "netscaler.tcp.errors $t0 $(v $tcp.81.0) $tags type=ReceivedDataAfterFin"
echo "netscaler.tcp.errors $t0 $(v $tcp.35.0) $tags type=ReceivedMultipleSynsAtHandshake"
echo "netscaler.tcp.errors $t0 $(v $tcp.38.0) $tags type=ReceivedInvalidAckAtHandshake"
echo "netscaler.tcp.errors $t0 $(v $tcp.36.0) $tags type=ReceivedSynAfterHandshake"
echo "netscaler.tcp.errors $t0 $(v $tcp.42.0) $tags type=ReceivedDuplicateFin"
echo "netscaler.tcp.errors $t0 $(v $tcp.44.0) $tags type=ReceivedRstForUnknownConn"
echo "netscaler.tcp.errors $t0 $(v $tcp.45.0) $tags type=ReceivedRstOutOfWindow"
echo "netscaler.tcp.errors $t0 $(v $tcp.46.0) $tags type=ReceivedRstAtTimewait"
echo "netscaler.tcp.errors $t0 $(v $tcp.83.0) $tags type=ReceivedDataOutOfWindow"
echo "netscaler.tcp.errors $t0 $(v $tcp.49.0) $tags type=ReceivedRetryFullPacket"
echo "netscaler.tcp.errors $t0 $(v $tcp.50.0) $tags type=ReceivedRetryPartialPacket"
echo "netscaler.tcp.errors $t0 $(v $tcp.48.0) $tags type=ReceivedRetry lbend=front"
echo "netscaler.tcp.errors $t0 $(v $tcp.47.0) $tags type=ReceivedRetry lbend=back"
echo "netscaler.tcp.errors $t0 $(v $tcp.52.0) $tags type=ReceivedUnorderedPacket lbend=front"
echo "netscaler.tcp.errors $t0 $(v $tcp.51.0) $tags type=ReceivedUnorderedPacket lbend=back"
echo "netscaler.tcp.errors $t0 $(v $tcp.39.0) $tags type=SentSynRetry"
echo "netscaler.tcp.errors $t0 $(v $tcp.74.0) $tags type=SentDataRetry attempt=1"
echo "netscaler.tcp.errors $t0 $(v $tcp.75.0) $tags type=SentDataRetry attempt=2"
echo "netscaler.tcp.errors $t0 $(v $tcp.76.0) $tags type=SentDataRetry attempt=3"
echo "netscaler.tcp.errors $t0 $(v $tcp.77.0) $tags type=SentDataRetry attempt=4"
echo "netscaler.tcp.errors $t0 $(v $tcp.78.0) $tags type=SentDataRetry attempt=5"
echo "netscaler.tcp.errors $t0 $(v $tcp.79.0) $tags type=SentDataRetry attempt=6"
echo "netscaler.tcp.errors $t0 $(v $tcp.80.0) $tags type=SentDataRetry attempt=7"
echo "netscaler.tcp.errors $t0 $(v $tcp.73.0) $tags type=SentDataRetry"
echo "netscaler.tcp.errors $t0 $(v $tcp.40.0) $tags type=SentFinRetry"
echo "netscaler.tcp.errors $t0 $(v $tcp.71.0) $tags type=SentRst"
echo "netscaler.tcp.errors $t0 $(v $tcp.37.0) $tags type=TerminationSynRetryFailure"
echo "netscaler.tcp.errors $t0 $(v $tcp.60.0) $tags type=TerminationDataRetryFailure"
echo "netscaler.tcp.errors $t0 $(v $tcp.41.0) $tags type=TerminationFinRetryFailure"
echo "netscaler.tcp.errors $t0 $(v $tcp.43.0) $tags type=TerminationReceivedRst"
echo "netscaler.tcp.errors $t0 $(v $tcp.68.0) $tags type=TerminationTimeWaitProfusion"
echo "netscaler.tcp.errors $t0 $(v $tcp.66.0) $tags type=QueueSyn lbend=back"
echo "netscaler.tcp.errors $t0 $(v $tcp.67.0) $tags type=DropSynQueueEviction lbend=back"
echo "netscaler.tcp.errors $t0 $(v $tcp.84.0) $tags type=DropSynCongestion"
echo "netscaler.tcp.errors $t0 $(v $tcp.82.0) $tags type=DropRstRateLimit"

# group port allocation failures
a=$(v $tcp.69.0)
b=$(v $tcp.70.0)
total=$(expr $a + $b)
echo "netscaler.tcp.errors $t0 $total $tags type=DropSynPortAllocError lbend=back"

# group syncookie failures
a=$(v $tcp.55.0)
b=$(v $tcp.56.0)
c=$(v $tcp.57.0)
d=$(v $tcp.58.0)
total=$(expr $a + $b + $c + $d)
echo "netscaler.tcp.errors $t0 $total $tags type=ReceivedInvalidSynCookie"

cd /
rm -r $datadir